The overarching goal of our project is to use IPSC derived cardiomyocytes from genotyped individuals as cellular models to investigate how human genetic variation influences the gene regulatory networks Involved In cardiac biology and disease. Despite current treatment regimens, cardiovascular diseases remain the leading cause of morbidity and mortality in the United States and developed countries. Genome-wide association studies have identified a number of loci associated with cardiovascular disease susceptibility. Our Study will clarify the functional significance of these findings by combining cellular reprogramming Strategies with integrated molecular profiling and cellular assays. We have assembled a team of highly accomplished researchers in stem cell biology, cardiac cell biology, genomics, molecular genetics/epigenetics, biostatistics, and clinical medicine, and are well positioned to achieve the project goals within five years. After collecting fibroblasts and keratinocytes from individuals in the UCSD TSP cohort, the project will be carried out in three phases. In PHASE I, we will establish standardized reagents and procedures for the generation of iPSCs. Additionally, we will take advantage of our ongoing research efforts to increase the efficiency of cardiomyocyte differentiation to 80%, a substantial increase over current protocols (~20%). In PHASE II, we will develop cutting-edge technologies for high throughput generation of IPSCs, which will enable us to generate 600 iPSC lines (3 lines each from 200 individuals) in ~ 24 months. We will also scale our optimized protocols for deriving cardiomyocytes from the IPSC lines. In PHASE III we will initially perform validation experiments to measure the genomic profile variability between isogenic (derived from the same individual) cardiomyocytes. We will then use the derived cardiomyocytes to 1) Identify and characterize the causal DNA variants underlying strong GWAS signals with electrocardiographic traits; and 2) Identify expressed quantitative traits loci (eQTL) in the cohort of IPSC derived cardiomyocytes at baseline (untreated) and after stimulation. (End of Abstract)